CSC364 Lecture 02

Introduction to Networked, Distributed, and Parallel Computing
Sockets
(202606)

Transcript

1. Dr. Javier Gonzalez-Sanchez javiergs@calpoly.edu www.javiergs.info o ffi ce: 14 -227 CSC 364 Introduction to Networked, Distributed, and Parallel Computing Lecture 02. Sockets 1
2. Socket Socket Socket Socket Socket
3. 3 Goal This is called a system, not just a program.
4. 4 Goal If we can make two programs talk to each other, everything else in the course has a place to land.
5. Fundamentals of Networking Concepts 5
6. 6 Campus Network
7. 7 Concepts • URL • Resource • Protocol • IP a ddress • Port • DNS • DNS a ddress • DNS server • Firew a ll • Client • Server • Socket
8. 8 Concepts Device A (IP address) 🏭 🏭 Port Port Port Port Port Port Port Port Socket Socket Device B (IP address)
9. 9 De f inition A socket is a bidirection a l byte stre a m between two processes (progr a ms) Import a nt: • Not mess a ges (text) • Not objects • Just bytes
10. 10 Why they matters? Sockets a re used everywhere: • HTTP servers • Multipl a yer g a mes • Distributed d a t a b a ses • ROS nodes S a me ide a s. Bigger sc a le.
11. 11 Client - Server Architecture Server 1. Cre a te socket 2. Bind to port 3. Listen 4. Accept connection Client 1. Cre a te socket 2. Connect to server 3. Send / receive d a t a
12. Note About your IP
13. 13 Localhost or 127.0.0.1 loc a lhost A hostn a me th a t me a ns this computer 127.0.0.1 The IP a ddress of the loopb a ck interf a ce ➡ Both refer to the s a me m a chine you a re running on
14. 14 How to Get Your IP Address m a cOS / Linux ifcon f ig Look for inet under en0 (Wi-Fi) or en1. Windows (Comm a nd Prompt or PowerShell) ipcon f ig Look for IPv4 Address.
15. Client-Server Sockets
16. Client-Server 16
17. Implementation :: Server 17 chrestomathy: https://www.javatpoint.com/socket-programming
18. Implementation :: Server 18
19. Implementation :: Client 19 chrestomathy: https://www.javatpoint.com/socket-programming
20. Implementation :: Client 20
21. 21 Homework Run the example Break it!
22. 22 Failure Is Normal Try this: • Kill the server • Disconnect the client • Send inv a lid d a t a Common errors: • Connection refused • Timeout
23. 23 Questions
24. Lab. Sockets
25. 25 Goal This is called a system, not just a program.
26. CSC 364 Introduction to Introduction to Networked, Distributed, and Parallel Computing Javier Gonzalez-Sanchez, Ph.D. javiergs@calpoly.edu Winter 2026 Copyright. These slides can only be used as study material for the class CSC 364 at Cal Poly. They cannot be distributed or used for another purpose. 26